Before you make your collage, give some thought to what's up for you astrologically. What is the New Moon activating? Which houses and planets are engaged? The New Moon brings the Sun and Moon into alignment in the same degree. Where does that fall in your own birth chart? What experiences have you had with these energies, and how do they relate to who you are today?
Let this be a question for awhile. Let the intuitive mind take over and guide you to themes for your collage. A few days before each New Moon, I like to carry it with me -- to the store, while waiting in line at the bank, in the garden. Then forget about it, and let the deeper process take over, and watch what pops up for you.